KURAG ELECTRONICS PLC-24V10AL User manual

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
TEC (Peltier) Controller
PLC-24V10AL
Reference Manual
(Rev.1.00)
Kurag Electronics LLC
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This reference manual explains detailed functions and advanced usage of the TEC (Peltier)
Controller PLC-24V10AL.
For basic usage, please refer to the quic start manual.
Than you for purchasing the TEC (Peltier) Controller PLC-24V10AL.
Read these operating instructions carefully to ensure effective use of all the performance
this product as to offer, and then use the product properly.
In particular, please be sure to read "Cautions on use" before use.
After reading these operating instructions, be sure to store them in a place where they can
be readily consulted whenever necessary.
Technical support and after-sales service
About support, such as an inquiry about this product, a request for repair, and download of
application software, and after-sale service, it is accepted at the Kurag Electronics website.
Please contact the address listed below.
K RAG ELECTRONICS WEB site: http://kurag.o.oo7.jp/kurag-el/
E-mail (Peltier Controller Support): k[email protected]

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
Table of content
1. Cautions on use Page 3
2. General Page 4
3. Contents Page 5
4. Names of parts and functions (Main board) Page 6
5. Names of parts and functions (Display board) Page 7
6. Setting and connection Page 8
6-1. Setting of power supply voltage Page 8
6-2. Setting of alarm / protection functions Page 10
6-3. Setting of temperature sensor type Page 11
6-4. Setting of PID control parameters Page 12
6-5. Connection Page 13
6-6. Connection diagram (Single power supply) Page 16
6-7. Connection diagram (Dual power supply) Page 16
7. Operation Page 17
7-1. Basic operation by ey operation Page 17
7-2. Temperature indication of sub temperature sensor Page 17
7-3. Operation procedure of continuous mode Page 17
7-4. Operation procedure of timer mode Page 18
7-5. Operation procedure of loc mode Page 19
8. Alarm / Protect / Indicator functions Page 20
8-1. Alarm functions Page 20
8-2. Reverse protection Page 21
8-3. Indicator function Page 22
9. Specifications Page 23
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
1. Caution on u e
✔The use of Kurag Electronics (KE) products with production equipment for the manufacture of
weapons of mass destruction (WMD) or any other weapon is strictly prohibited.
✔The exports of KE products or technology from one country to another are governed by the relevant
security laws and regulation of the countries involved in the transaction. Prior to shipment of KE
product to another country, assure that all local rules governing that export are nown and followed.
✔You agree to comply with all applicable international and national laws that apply to the Product,
including Japanese Export Trade Control Order, as well as end-user, end-use, and destination
restrictions issued by Japanese and other governments.
✔We can bear absolutely no responsibility whatsoever for any direct or indirect damage that may
occur due to the use of this product in your applications.
✔This product is to be used with general industrial product. This product is not designed or
manufactured to be used under such special conditions and environments as nuclear energy control,
aerospace, transportation, medical equipment, various safety equipment or equipment which require
high level reliability related human life. We assume no liability for any direct or indirect damages
that may occur due to applying this product to such equipment or apparatus.
✔If you notice smo e, strange smells or noise coming from the product, cut off the power supply.
Continued use of the product in these conditions will result in fire or electric shoc .
✔If a liquid li e water or foreign objects li e pins and clips which have conductivity adhere to the
product, cut off the power supply immediately. Continued use of the product in these conditions will
result in fire or electric shoc .
✔If the product is dropped or strongly shoc ed or excess power added, cut off the power supply
immediately. Continued use of the product in these conditions will result in fire or electric shoc .
✔When electric power is connected to the product, be careful to apply the proper voltage specified in
the product specification. Improper voltage may cause malfunction or destroy the circuit. Moreover,
please do not use it with the power supply voltage exceeding the rated voltage/current of the Peltier
device to be connected. (A same voltage is supplied to the Peltier device.) Please confirm the
polarity of connections. If a mista e made, regarding polarity, it may result in fire or electric shoc ,
and it may cause malfunction of the product or Peltier device.
✔When you install this product into equipment or wiring the circuit, don’t turn on the power until
wor is completed. A large current flows into wiring of a power supply or a Peltier device. So please
select the wiring material with suitable diameters.
✔Do not operate at temperatures or humidity, etc. beyond the range of specifications.
✔Please do not use it in a dusty place, the place where direct sun beam hit and the environment where
corrosive gases exist. If a dew condensation is generated, you should not use the product until it dries
completely.
✔Never attempt to perform dismantle or modification. And when the product brea s down, do not
repair it by yourself. If the product bro e down, please consult to our support dept.
✔Failure to heed this instruction may cause in fire, electric shoc , personal injury or malfunction.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
1. Caution on u e (continued)
✔Do not touch directly the electrical components which are mounted on the printed wiring board. And
please ta e care not to charge the static electricity to the electrical components.
✔To transport this product, it should be put in the shipping carton, or please put a printed circuit board
into an anti-static bag or a conductive bag, and pac up using suitable shoc absorbing material so
that vibration and a shoc are not added.
✔Dispose of the product according to all national laws and regulations.
2. General
✔PLC-24V10AL-PT and PLC-24V10AL-TH are TEC (Peltier) temperature controller.
✔The differences of the specification from the base model PLC-24V10A are as follows.
Item PLC-24V10A PLC-24V10AL-PT PLC-24V10AL-TH
Main temperature sensor Pt100 / NTC thermistor Pt100 NTC thermistor (*1)
Peltier driving voltage 3V to 24V 7V to 24V(*2)
Temperature range Pt100: -50℃ to 150℃
NTC thermistor: -40℃ to 100℃
-40℃ to 100℃
DC Fan output Direct / 5V fixed / 12V fixed Direct
(*1) NTC thermistor R25 =10 ohm. It is selectable the type of NTC thermistor by using the dedicated setting software.
(*2) Driving voltage depends on supply voltage. It can be driven from 0.5 V for dual power supply operation.
✔High driving current up to 10A by the PWM drive
✔The digital PID control
✔Sub temperature sensor for monitoring (NTC thermistor R25 =10 ohm)
✔Temperature monitoring function (indicator function)
✔DC fan connection terminal with rotational pulse input
✔Continuous operation and timer operation by stand-alone operation
✔Stac able display board for stand-alone operation
✔When an alarm occurs, the cause code of the alarm is displayed on the display board.
✔External control input (Start / Timer) / Parallel output (Indicator / Alarm)
✔Operation loc function to prevent mis-operation
✔Same form factor (same dimension) as previous model of PLC series (PLC-24V6A, etc.)
✔RS-232 serial communication port
✔It is possible to control from the personal computer by using RS-232 serial command.
✔Free control software and setting software are available from Kurag Electronics website.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
3. Content
Listed items are included in this product pac age.
Please chec that these items are included.
Name Main board Display board Main with display
PLC-24V10AL Main Board ✔ ✔
PLC-24V10A Display Board ✔ ✔
RS-232 Cable ✔ ✔
Quic Start Manual ✔ ✔ ✔
Main board Display board
RS-232 cable
* JST XHP-3 to Dsub 9 pin Cable length = 100mm
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
4. Name of part and function (Main board)
1. Power supply terminal
The range of supply voltage is DC 7V to 24V (single power supply).
2. TEC (Peltier) element terminal
3. Sub temperature sensor terminal
4. Main temperature sensor terminal
5. / 6. Connectors to Display Board
7. DC fan terminal
DC fan terminal for heat sin ing. (up to 500 mA)
The same voltage as power supply voltage can be outputted for a standard product.
The fixed voltage of 5V or 12V can be outputted for a customized product.
8. A connector for a RS-232 communication cable
Connector to connect an attached RS-232 cable for external control.
9. The connector for factory use (no part is mounted)
10. / 11. A terminal for external control (START / TIMER)
A start/stop of temperature control operation and timer operation are controllable by
connecting and switching on and off for these terminals.
12. / 13. Parallel output (INDICATOR / ALARM)
Open collector outputs to notify the indicator and alarm status.
14. / 15. Status LED lamps (R N / ALARM)
LED lamps to display the product operation status.
14. RUN: Turn-on during control operation. Blin ing during reverse protection
15. ALM; Blin ing when alarm occur. Turn-on during temperature indicator wor s.
* When the display board is connected, these LED lamps are turned-off.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
5. Name of part and function (Di play board)
1. / 2. Connectors to Main Board
The connectors combine a display board with a main board.
3. / 4. / 5. Operation status LED lamps
These LED lamps display the product operation status.
3. The temperature control is at wor : Lights up “RUN” (GREEN)
4. The heater mode is at wor : Lights up “HEAT” (RED)
5. The cooler mode is at wor : Lights up “COOL” (GREEN)
6. Alarm LED lamp
When alarm occurred, blin s “ALARM” (RED) and the operation is stopped.
7. / 8. / 9. Display status LED lamps
These LED lamps display the content of 7 segments LED displays. It blin s during
a setting and lights up continuously after decision or during display.
7. Display the temperature: Lights up “TEMP.” (YELLOW)
8. Display the time (unit: minute): Lights up “MIN.” (YELLOW)
9. Display the time (unit: hour): Lights up “HOUR.” (YELLOW)
10. 7 segment LED (4 digit)
This LED displays the temperature or time.
11. MODE key 12. DOWN key 13. P key 14. SET key
These eys are for setting of temperature or timer operation.
15. Operation switch
Position of switch is upper side ON: Start
Position of switch is lower side OFF: Stop
SW1: Start/Stop the continuous operation.
SW2: Start/Stop the timer operation.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6. Setting and connection
6-1. Setting of power upply voltage
This product uses PWM drive. The drive circuit is configured as shown below.
This figure shows the state when driving in the cooling direction. A switching element of a full
bridge configuration (actually a semiconductor switch element) by switching on / off the
polarity of the Peltier drive output and performing PWM modulation, temperature control is
carried out. Since the voltage drop of the switching element and current detection circuit is very
small, the driving voltage “VPD” of the Peltier element is almost equal to the power supply
voltage “VP”.
* In this product, the filter circuit is not included in the Peltier drive output, so during PWM
drive a pulse whose voltage is almost equal to the power supply voltage VP is applied to the
Peltier device.
The equivalent circuit when voltage is applied to the Peltier element is as shown below.
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VPD: Peltier driving voltage
IPD: Peltier driving current
RP: Internal resistance of Peltier
VSB: Thermo-electromotive force due to Seebec effect
* VSB increases as the temperature difference between
the heat absorption surface and the heat radiation
surface of the Peltier element increases.

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
Peltier driving current IPD is calculated by the following formula.
IPD=(VPD-VSB)/RP
The voltage of the Peltier drive power supply (VP) is needed to set to satisfy the following
conditions (1) to (3).
(1) VP ≈ VPD ≤ Vmax (Vmax: maximum voltage of the Peltier element)
(2) IPD = (VPD - VSB) / RP ≤ Imax (Imax: maximum current of the Peltier element)
In case that temperature control is always performed at a constant temperature, when VSB = 0
in equation (2), IPD is the maximum. When there is no temperature difference between both
surface (for example at the start of temperature control), VSB will be “0”.
(2-1) IPD = VPD / RP ≤ Imax -> VPD = IPD x RP ≤ Imax x RP
When repeating cooling / heating, at the moment the driving polarity reverses, the polarity of
VSB becomes reverse polarity as the polarity of VPD, IPD will be increased.
(2-2) IPD = (VPD + VSB) / RP ≤ Imax -> VPD = IPD x RP - VSB ≤ Imax x RP - VSB
* By using the drive reversal protection function, excessive current flows in the Peltier element
when the drive polarity reverses It can prevent flowing.
For details, please refer to "8-2. Drive reversal protection function" in this document
In addition, the power supply voltage range restricted by the specifications of this product is as
follows.
(3-1) 7V ≤ VP ≤ 24V (Single power supply)
(3-2) 0.5V ≤ VP ≤ 24V (Dual power supply)
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6-2. Setting of alarm / protection function
For alarm / protection function, use the dedicated setting software "PLC-24V10A Manager"
You can enable / disable and set alarm detection judgment value by using.
* For the display of the cause code of the alarm, please refer to "8-1. Alarm function"
The following table shows the guidelines for describing and setting each alarm / protection
function.
Name Description Guideline
Temperature sensor
(Main sensor)
An alarm occurs when the main temperature
sensor is not connected or disconnected.
It is recommended to set it to “ON” (Enable).
Temperature sensor
(Sub sensor)
An alarm occurs when the sub temperature sensor
is not connected or disconnected.
When the sub temperature sensor is used, it is
recommended to set it to “ON” (Enable).
Power supply An alarm occurs when the power supply voltage is
out of the preset reference range.
It is normally “OFF” (Disable) and it is no
problem. When the power supply voltage is
changed dynamically, set it to “ON” (Enable).
Peltier current An alarm occurs when the Peltier current is out of
the preset reference value range.
It is recommended to set it to ON (Enable).
Please set the lower limit to 1/10 to 1/5 of the
normal current of the Peltier element.
Please set the upper limit to less than the
maximum current (Imax) of the Peltier element.
Fan stop When using DC fan with pulse sensor (3 wire
type), rotation pulse from fan is not detected about
5 seconds or more, an alarm occurs.
If you do not connect a DC fan with a pulse
sensor, set it to OFF (Disable).
Peltier polarity An alarm occurs when the temperature control
operation is continued with the polarity of the
Peltier element reversely connected
If the Peltier element is connected to the correct
polarity, it is normally OFF (Disable) and there is
no problem.
Reverse protection When the drive polarity is reversed, the
temperature control operation is temporarily
stopped, and the Peltier element is protected from
over current. (It restarts automatically)
In case of repeating cooling / heating, turn ON
(Enable) when power supply voltage VP can not
satisfy the condition of (2-2) of “6-1. Setting of
power supply voltage”.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6-3. Setting of temperature en or type
It is able to select the temperature sensor type by using the dedicated setting software
"PLC-24V10A Manager". When ordering, if you specify the temperature sensor type, we will
deliver it with the setting corresponding to that temperature sensor.
* Please chec the shipment inspection report attached to the product.
If you did not specify the temperature sensor at the time of shipping, the temperature sensor
type is set as follows.
Name Setting of temperature sensor type Temperature
range
Enable
/ Disable
Main temperature
sensor
-PT: Pt100 Platinum RTD R(0℃)=100ohm
-TH: SEMITEC 103JT NTC thermistor R25=10 ohm B(25/85)=3435K
-40°C to +100°C Always
enable
Sub temperature
sensor
SEMITEC 103JT
NTC thermistor R25=10 ohm B(25/85)=3435K
-40°C to +100°C Disable
* The setting of the temperature range can be made narrower than the range above, but it can not be expanded.
The following temperature sensor type can be selected.
* The NTC thermistor can also be set by entering coefficients of the Steinhart-Hart approximate expression.
Name Supplier Parts # ("x" is arbitrary) Main sensor Sub sensor
-PT -TH
Pt100 - - ✔- -
SEMITEC 103JT SEMITEC 103JT-xxx - ✔ ✔
SEMITEC 103ET SEMITEC 103ET-x-1P - ✔ ✔
SEMITEC 103AT SEMITEC 103AT-x - ✔ ✔
SEMITEC 103KT SEMITEC 103KT1608T-1P - ✔ ✔
MURATA NXFT15XH103 Murata NXFT15XH103FAxBxxx - ✔ ✔
MURATA NXFT15XV103 Murata NXFT15XV103FAxBxxx - ✔ ✔
OMEGA 44006/44031 OMEGA 44006 or 44031 - ✔ ✔
VISHAY NTCLE100E3103 VISHAY NTCLE100E3103JB0 - ✔ ✔
EPCOS B57861S0103 EPCOS (TDK) B57861S103F040 - ✔ ✔
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6-4. Setting of PID control parameter
It is able to change the parameter (coefficient) of PID control by using the dedicated setting
software "PLC-24V10A Manager".
Guidelines of setting are as follows.
Preset# Response of the temperature sensor Guideline of setting
Kp Ki Kd
9The sensor is located close to the temperature control
surface. Temperature change can be detected with no time
lag.
500 0.7 0
5The sensor is slightly away from the temperature control
surface. Temperature change can be detected with a delay
of few seconds.
100 0.3 0
1And the temperature change is detected with a delay of
about several seconds.
The sensor is far away from the temperature control
surface of the Peltier element
, And the temperature change is detected with a delay of
10 seconds or more.
15 0.1 0
* If the control is unstable, adjust the parameters according to the technical manual
"PLC-24V10A PID control parameter setting".
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6-5. Connection
To connect the screw terminal bloc , please strip the covering of an electric wire about 5 mm, and
insert to the terminal and eep certain tightening torque using screwdriver.
The wire material that is compatible with the screw-type terminal is as follows.
Conductor cross section: 0.05 mm² to 1.31 mm² (AWG # 30 to AWG # 16)
* Please fully loosen the screw before inserting the electric wire.
(1) Connecting the display board to the main board
* The connection is already established in case of main with display set.
Please align the direction of a substrate, and the position of two connectors, and insert straightly.
If the direction is wrong or the position of each connector is shifted, you can not perform the
connection physically. In that case, please do not insert by force.
(2) Connecting power supply
Connection method differs depending on single power supply and dual power supply.
Also, in order to switch between single power supply and dual power supply, it is necessary to
open / short the solder short pad on the bac of the main board with a soldering iron.
* When there is no designation at the time of ordering, it is set for single power supply.
Name Terminal
Fan output direct
Single power supply Dual power supply
SPx SP2 Short Open
SP3 Open Short
SP4 Short Short
SP5 Short Open
SP6 Open Open
POWER VP + (DC 7V to 24V) For Peltier drive + (DC 0.5V to 24V)
GND - (GND) For Peltier drive - (GND)
FAN F+ Connect DC Fan For control circuit + (DC 7V～24V)
F- For control circuit - (GND)
* Please use a wiring material with sufficient current capacity.
Position of short pad (Bottom side of main board)
* Resettable fuses may be mounted between SP2 and SP3 depending on production lot.
* The picture shows the setting of dual power supply. (SP 2 is open, SP 3 is short, SP 5 is open)
* SP1 is a short pad for connecting circuit GND to FG (chassis ground).
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
(3) Connecting Peltier element
Name Pin Connection
PELTIER PL+ Please connect the each lead wire of Peltier device respectively as follows.
The surface of Peltier device which should be temperature-controlled is
cooling when a current flows from PL+ to PL-.PL-
* Please use a wiring material with sufficient current capacity.
(4) Connecting temperature sensor
Name Pin
PLC-24V10AL-PT PLC-24V10AL-TH
3-wire Pt sensor 2-wire Pt sensor NTC thermistor
MAIN SENSOR A/TH+ A A Th+
B1/TH- B B Th-
B2 B Short with B1/TH- Open
Name Pin NTC thermistor
SUB SENSOR STH+ Th+
STH- Th-
* Only NTC thermistor is supported as the sub sensor. Pt sensor can not be connected to the sub sensor.
(5) Connecting DC fan
Name Pin Connection
FAN F- GND
F+ Vcc * Please connect after chec ing the rated voltage of the fan motor.
FS PULSE * Please connect if a pulse sensor is equipped.
* In case of a standard product, the same voltage as power supply voltage is output to F+ (Vcc).
* In case of a customized product, the fixed voltage of 5V or 12V is output to F+ (Vcc).
(6) Connecting of communication cable
When you want to operate this product by communication commands, please connect the attached
RS-232 communication cable.
*Do not connect any cable except for the attached RS-232 communication cable.
Location of connection terminals
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A/TH+ B1/TH- B2
MAIN SENSOR
STH+ STH-
SUB SENSOR
PL+ PL-
PELTIER
VP GND
POWER
F- F+ FS
FAN
Connector
for RS-232 cable

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
(7) Connection of main board external control terminal
It is a 2.54 mm pitch pin header.
Short soc et, switch, photo coupler, relay etc. between terminals
By shorting / opening, it is possible to start / stop the temperature control operation and
start / stop the timer operation.
* It has the same function as the operation control switch of the display unit (equivalent to
being connected in parallel).
* Since it is pulled up by the internal circuit, please do not apply the voltage signal.
(8) Connection of main unit parallel output terminal
It is a 2.54 mm pitch pin header.
It is two open collector outputs, and it is output as follows depending on the indicator and
alarm occurrence situation.
Name Temperature is within
the reference range
Temperature is out of
the reference range
TEMPID OPEN LOW
Name No alarm has occurred An alarm has occurred
ALARM OPEN LOW
* The GND terminal is connected to the internal circuit GND and is not insulated.
When connecting to an external circuit, please insulate with photo coupler etc.
as necessary.
* When pulling up to the outside, ma e sure that the voltage is 24 V or less and the current
is 50 mA or less.
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START
Input
GND GND
TIMER
Input
TEMP ID
Output
GND GND
ALARM
Output

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
6-6. Connection diagram (Single power upply)
6-7. Connection diagram (Dual power upply)
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* When the wiring of the temperature sensor is long,
it is recommended to use a shielded wire to reduce
the influence of external noise.
* When 2-wire Pt100 sensor is used,
short-circuit between the B1 terminal
and the B2 terminal.

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
7. Operation
There are two types of modes that can be operated as “Continuous mode” and “Timer mode”.
In addition, you can select either “Timer mode” or “Loc mode” by using the dedicated
setting software "PLC-24V10A Manager".
* When the loc mode is selected, the operation procedure will change, timer operation can not be performed
by stand-alone operation. Even in this case, timer operation by communication command is possible.
* When there is no designation at the time of ordering, it is set "Timer mode".
7-1. Ba ic operation by key operation (when “Timer mode” is selected)
Every time when MODE ey is pushed, the display of 7 segment LED changes as follows.
Current temperature Push SET ey Remaining Time (*)
Push MODE ey
Push SET ey Target temperature setting
Push MODE ey
Push SET ey Timer Setting (Unit: minute)
Push MODE ey
Push SET ey Timer Setting (Unit: hour)
Push MODE ey
7-2. Temperature indication of ub temperature en or
If you press and hold the MODE ey during the current temperature display, the temperature of
the sub temperature sensor will be displayed while pressing the MODE ey. TEMP. LED turns
off during sub temperature sensor temperature display.
Release the MODE ey to return to the temperature display of the main temperature sensor.
* If the sub temperature sensor is disabled or the sub temperature sensor is not connected, the incorrect
temperature may be displayed.
7-3. Operation procedure of continuou mode (when “Timer mode” is selected)
1) Pressing the MODE ey to change the display to the target temperature setting mode.
(TEMP. LED blin s)
2) Set the desired temperature using UP/DOWN eys.
* A fast setting is available by pressing the button continuously.
* The target temperature can be set within the preset temperature range.
3) Pressing SET ey to complete the target temperature. (Displays current temperature)
4) Slide the START switch to “ON”. (Start the temperature control)
5) Slide the START switch to “OFF”. (Stop the temperature control)
* The target temperature is stored in the memory even if the power is turned off.
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(*)Displays “---- “ at continuous operation mode.

PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
7-4. Operation procedure of timer mode
1) Set the target temperature using UP/DOWN eys as same as continuous mode.
2) Press the MODE ey to display the timer setting mode (unit: minute or hour).
(MIN. or HOUR LED blin s)
3) Press the UP/DOWN eys to change the timer setting.
* A fast setting is available by pressing the button continuously.
4) Press the SET ey to complete the timer setting. (Displays current temperature)
* The unit of “minute” or “hour” which was set up at the last becomes effective.
5) Slide the timer switch of this unit to “ON”. (Start the timer)
* If a start switch is already “ON”, the timer mode is started from that point.
* If a START switch is turned off, slide both of START switch and TIMER switch to “ON”
simultaneously.
6) A remaining time of timer is displayed if the SET ey is pressed.
(Displays current temperature if the SET ey is pressed again)
7) When the timer reached the setup time, the operation is automatically stopped.
* If a TIMER switch is turned off before the end of a timer, temperature control is ept in the
continuous mode.
* If a TIMER switch is turned off and turned on again, the timer will start again from the beginning.
* The setting of the timer is stored in the memory even if the power is turned off.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
7-5. Operation procedure of lock mode (when lock mode is selected)
The loc mode is a mode to restrict operation so that careless target temperature setting is not
changed.
During the loc mode, the LOCK LED on the indicator lights up.
Temperature control start / stop operation with START switch is also possible in loc mode.
The state of the operation restriction changes with ON / OFF of the operation switch LOCK.
When the LOCK switch is ON
The target temperature can not be changed.
Each time the MODE ey is pressed, the display of the current temperature and the target
temperature is toggled.
PV LED turns on -> Current temperature is displayed
Press the MODE ey
SV LED turns on ->Target temperature is displayed
Press the MODE ey
When the LOCK switch is OFF
The target temperature can be changed by the following procedure.
(1) Press and hold the SET ey until the SV LED blin s.
(2) Press the UP / DOWN ey to change the target temperature.
* When the upper limit and lower limit of the set temperature range are reached, even if you press the
UP / DOWN ey, the number does not change.
(3) Press the SET ey to set the target temperature.
* The PV LED lights up and returns to the current temperature display.
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PLC-24V10AL Reference Manual (Rev.1.00) Kurag Electronics LLC
8. Alarm / Protect / Indicator function
Each function can be set to ON or OFF by the dedicated software.
Moreover, change of a detection reference value can be changed about some functions.
8-1. Alarm function
This product has the following alarm functions. When an alarm occurs, the alarm indication
LED blin s, the cause code is displayed on the indicator, and the temperature control operation
stops.
Turn off the temperature control switch once, remove the cause of alarm, turn it on again and
the temperature control operation resumes.
Name Cause code Description
Temperature
sensor
Main: - - - 1
Sub: - - - 7
An alarm occurs when the temperature sensor is not connected or disconnected.
Power supply Under: - - - 3
Over: - - - 4
An alarm occurs when the power supply voltage is out of the preset reference range.
Peltier current Under: - - - 5
Over: - - - 6
An alarm occurs when the Peltier current is out of the preset reference value range.
Fan stop - - - 2 When using DC fan with pulse sensor (3 wire type), rotation pulse from fan is not detected
about 5 seconds or more, an alarm occurs.
Peltier polarity - - - 8 An alarm occurs when the temperature control operation is continued with the polarity of
the Peltier element reversely connected
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